1. Field of the Invention
The present invention relates to a rolling bellows for pneumatic cushioning or shock absorption of a vehicle. The rolling bellows is in the form of a cylindrical tube body of rubber or rubber-like synthetic material, and is provided with reinforcing inserts. In the installed state, the rolling bellows is supported against the outer surface of a rigid rolling cylinder while forming a cylindrical curvature.
2. Description of the Prior Art
The movable cylindrical curvature of the installed rolling bellows, which is subjected to the operational air pressure, collapses along with the constantly changing transition between different bellows diameters. Therefore, already with the insertion of such pneumatic cushioning bellows into the vehicle structure, the cylindrical curvature must appear at a location which is particularly prone to tension cracks. The first experiences with the new type of cushioning system apparently proved this to be correct. The endeavors based hereon for improving the rolling bellows led to the known proposal of U.S. Pat. No. 3,598,155--Burkley dated Aug. 10, 1971 and corresponding German Pat. No. 1 806 927 of providing the inner surface of the cylindrical curvature with grooves which extend in the circumferential direction pursuant to the disposition pattern which results from the stresses during use. The development of new elastomeric materials and construction measures for the rolling bellows, and the use of improved manufacturing methods, allowed the original significance of this type of damage to become less important. Instead, as much more important there has now surfaced the problem of the crease-free telescoping of the bellows in the pressureless state during the course of assembly, and especially under the limited space conditions of the chassis; associated with this problem is the facilitated rolling in the pressureless state under emergency conditions. No improvements toward this end could be achieved with the heretofore known solution of molding peripheral grooves in the walls of the bellows.
An object of the present invention therefore is to overcome this particular problem with a novel construction of the pneumatic cushioning bellows, and to affect the rolling conditions in the pressureless state of the bellows in such a way that the danger of premature destruction as a result of the formation of creases or cracks is practically eliminated.